Pathologic changes of gastric mucosa colonized by Helicobacter pylori.

One hundred eighty-nine consecutive gastric biopsies showing colonization by Helicobacter pylori (HP) were studied. Epigastric pain and bleeding were the clinical presentations in 167 cases (88.4%). Major endoscopic findings were gastritis (n = 72, 38.1%) and ulceration (n = 101, 53.4%). Duodenal ulcer was associated with 32 (44.4%) and 29 (28.7%) cases of gastritis and gastric ulcer, respectively. Histologically, the HP-colonized gastric epithelium showed characteristic degenerative changes that were topographically related to the bacteria but unrelated to the inflammatory infiltrate. Disintegration and loss of apical mucus with formation of epithelial pits was seen in nearly all cases. Other changes included microerosion, conventional erosion, and frank ulceration. Only the disintegration of apical mucus, epithelial pit, and microerosion were specific for HP colonization. These conditions were absent in areas not colonized by HP and in 79 consecutive HP-negative gastric biopsies seen during the same study period. The epithelial degenerative changes in HP-colonized gastric mucosa are easy to recognize in routine hematoxylin-eosin-stained sections and they could serve as histologic guides to the localization of the bacteria. It is proposed that HP-colonized gastric mucosa is a distinct pathologic entity with a pathologic spectrum ranging from active chronic gastritis to erosion and frank ulcer. Damage to the mucin-containing portion of the gastric epithelial cells appears to be the basic cytopathologic effect of HP on the gastric mucosa. As effective specific treatment for HP infection is available, identification of HP colonization in gastric biopsies should be attempted in all cases of gastritis and gastric ulcer.